Alterations in the regulation of mitosis or cell cycle progression play an important role in diseases such as neoplasia and anemia. Manipulation of genes involved in regulating the cell cycle can be used to prevent or treat these diseases. Detections of mutations in cell-cycle regulatory genes can also be used to detect neoplastic cells and genetic predispositions to neoplasias. Thus, there is a need in the art for the identification of cell cycle regulator genes which can be used in methods of diagnosing, prognosing, and treating neoplasia and other diseases in humans and other mammals.